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Security paranoia

By 3xp3rt ·
IT security have no limits. I know a lot of techniques what are implemented in different locations, for hide the important information, beginning from a simple key locked door to fingerprint identification and so?.
But the ultimate technique for information thief is really painful.
There are two very interesting technologies to see your display from distance.

1. Optical Time-Domain Eavesdropping Risks of CRT Displays

The overall light emitted by a commonly used cathode-ray tube computer monitor is a broadband information carrier that transmits via light-intensity modulation the low-pass filtered video signal. It is feasible to reconstruct screen contents from this information channel, even if the eavesdropper cannot position a sensor within a direct line-of-sight to the target display surface and receives the light only after diffuse reflection, for instance from an office wall

2. Electromagnetic Radiation from Video Display Units

It is possible in some cases to obtain information on the signals used inside the equipment when the radiation is picked up and the received signals are decoded. Especially in the case of digital equipment this possibility constitutes a problem, because remote reconstruction of signals inside the equipment may enable reconstruction of the data the equipment is processing.
If no preventive measures are taken, eavesdropping on a video display unit is possible at several hundreds of meters distance, using only a normal black-and-white TV receiver, a directional antenna and an antenna amplifier. It is even possible to pick up information from some types of video display units at a distance of over 1 kilometer. If more sophisticated receiving and decoding equipment is used, the maximum distance can be much greater.

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Not new

by JamesRL In reply to Security paranoia

This is the reason why the "Tempest" standard exists, and Tempest has been around for at least 15 years.

At the last place I worked which required such security, they had a simpler solution. They applied a tinted film to the windows which significantly reduced the amount of EM radition. We also had restricted parking lots and cameras to make sure no one parked on the street and monitored us.

You should also note that LCD monitors produce much less radiation.

The problem with this technique is that in an office with hundreds of people, you need to determine who has the information you are interested in and when they access it. And of course they have to be in an office with a window. And you can only monitor one person at a time.

Its not as simple as you think. It would really require someone on the inside to assist with the setup. As one of those with the window office, I spent very little time looking at things that were either secret or commerically valuable. You might sit there for months reading my screen, go for a coffee and miss the only opportunity to see something of value. And I was cleared for "secret".


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Agree, but!

by 3xp3rt In reply to Not new

I agree with you. But it?s Ok in a full office. But what we do with server room?
Because if someone need an information from one network, and he have administrator password, the job is done. He don?t need the information itself from display, he can take that from HDD.

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But using those techniques

by JamesRL In reply to Agree, but!

The person doing the spying would have to be able to access the workstation of the administrator. The server room is typically in a basement with no windows because its easier to keep a consistent temperature there. Your technique would be blocked by a few inches of concrete.


I should add that these techniques work great under ideal conditions, but most office are far from ideal conditions. Yes you can read the emissions from a computer one kilometer away if there are few or no other emission sources between you and the source you want, and you know where to look. Don't forget that TVs, Radios, photocopiers etc all give off emissions that would interfere with the attempt to pick up the data. And the steel in buildings, a 12 inch thick concrete wall(laced with steel rebar), copper wiring, power transformers all make it more difficult if not impossible to gather emissions through.


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remote possibility

by Dr Dij In reply to But using those technique ...

since 1) the hacker needs physical proximity to building, most hackers like to be far away and anonymous from their target. 2) it requires van full of expensive gear, so would tend to be used only for big $ gains, by spooks or industrial spies.

when they can send spyware or keyloggers over and get someone to install it on your net or use STUPID windows crashes like wmp and jpeg flaws, they most likely have easier way to break in.

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Just for Info

by 3xp3rt In reply to But using those technique ...

If you want detailed information about this I can mail to you those two articles in PDF format. It?s very interesting. I?m sure this techniques was used by agencies, years, but probably now they have new techniques.

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See thru walls

by Dr Dij In reply to Just for Info

did you see the new device? Law enforcement officials (or spooks) can use this to see thru up to 12" of concrete. Has a blurry out line but shows people moving in a room.

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New Devices are old?

by 3xp3rt In reply to See thru walls

I don't know how new are, because how I sad in previous post I suppose the new techniques are top secret, and we can get this information after appearance of newest techniques.

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